1.Feasibility of computer-aided nodule detection system in digital chest radiographs
Yan XU ; Da-Qing MA ; Wen HE ;
Chinese Journal of Radiology 2000;0(11):-
Objective To assess the usefulness of a computer-aided detection(CAD)system on detecting the pulmonary nodules in digital chest radiography.Methods Three hundred and twenty-eight digital chest radiographies along with corresponding chest computed tomography were selected for this study. Two senior chest radiologists interpreted these cases using the CAD system and marked the locations and sizes of all nodules with consensus,which were stored in a computer system as Gold Standard to evaluate the performance of the CAD system.Eight radiologists of various experience read these selected cases without and with the aid of CAD system and their results were stored in a computer system.The radiologists' performance was evaluated by using the receiver operating characteristic analysis.Comparison is made regarding the difference in Az values when CAD was not used versus when CAD was used by using the paired-samples t test.Results For small nodules,the sensitivity of this computer system used by the two senior chest radiologists in 100 digital radiographs was 78.1%(118.0/151).Without and with the assistance of CAD system,the nodule detection sensitivity of the radiology residents was 62.4% (94.2/151),77.4%(116.8/151)respectively,and the area under the curve of radiology residents was 0.769,0.836 respectively.Statistical analysis showed there was statistically significant difference between interpretation without and with the CAD system(P0.05).Conclusions This CAD system can help to enhance the radiologists' ability to detect small pulmonary nodules.This is especially helpful for radiology residents.
3.Abdominal imaging in AIDS patients
Da-Wei ZHAO ; Tong ZHANG ; Wei WANG ; Chun-Wang YUAN ; Cui-Yu JIA ; Xuan ZHAO ; Da-Qing MA ;
Chinese Journal of Radiology 2001;0(03):-
Objective To evaluate abdominal imaging in AIDS.Methods The imaging examinations(including US,CT and MR)of 6 patients with AIDS associated abdominal foci were analysed retrospectively.All the cases were performed US,and CT scan,of which 4 performed enhanced CT scan and 1 with MR.Results Abdominal tuberculosis were found in 4 patients,including abdominal lymph nodes tuberculosis(3 cases)and pancreatic tuberculosis(1 case).The imaging of lymph nodes tuberculosis typically showed enlarged peripheral rim enhancement with central low-attenuation on contrast-enhanced CT. Pancreatic tuberculosis demonstrated low-attenuation area in pancreatic head and slightly peripheral enhancement.Disseminated Kaposi's sarcoma was seen in 1 case:CT and MRI scan demonstrated tumour infiltrated along hepatic portal vein and bronchovascular bundles.Pelvic tumor was observed in 1 case:CT scan showed large mass with thick and irregular wall and central low attenuation liquefacient necrotic area in the pelvic cavity.Conclusion The imaging findings of AIDS with abdominal foci is extraordinarily helpful to the diagnosis of such disease.Tissue biopsy is needed to confirm the diagnosis.
5.Significance of ~(99m)Tc-Diethyl Iminodiacetic Acid Hepatobliliary Planar and Tomographic Scintigraphy in Diagnosis on Biliary Atresia
ji-gang, YANG ; da-qing, MA ; chun-lin, LI ; lan-fang, ZOU
Journal of Applied Clinical Pediatrics 2006;0(19):-
Objective To evaluate the clinical value of 6 h 99mTc-diethyl iminodiacetic acid (99mTc-EHIDA) planar hepatobiliary scintigraphy (HBS),6 h tomographic HBS and 24 h planar HBS in diagnosis on biliary atresia(BA).Methods Seventy cases(32 male,38 female) with continuous jaundice received planar and tomographic HBS in Beijing Friendship Hospital from Jan.2005 to Dec.2007.The mean age was 48.7 d (29 d-4 months).According to final diagnosis,all cases were divided into BA group (45 cases) and non-BA group (25 cases).All cases fasted at least 4 hours before HBS.The equipment was 3 head IRIX from Philips company with low energy high resolution collimator.The tracer was 99mTc-EHIDA and the radiochemistry purity was more than 95 percent.The dosage was 7.4 MBq/kg.All diagnosis demonstrated by operation pathology and clinical follow-up.All cases received HBS at 5,10,15,20,30 min and 1,6 h after tracer injection.HBS would ended if radioactivity appeared in gallbladder or intestine.These cases would received tomographic HBS and 24 h HBS if radioactivity did not appear in gallbladder or intestine at 6 h post injection.All these images were analyzed by 2 or more nuclear medicine physicians.Results There were not radioactivity appearing in gallbladder and intestine on planar and tomographic HBS of 27 cases,which suggested the BA.There were radioactivity appearing in gallbladder and intestine on planar and tomographic HBS of 30 cases,which suggested the non-BA.Positive rate of 6 h tomographic HBS was significantly higher than that of 6 h planar HBS and there was significantly difference between the 2 methods.Positive rate of 6 h tomographic HBS was significantly higher than that of 24 h planar HBS and there was significant difference between the 2 methods.Conclusions 99mTc-EHIDA HBS is a noninvasive,safety,valuable examing method and has definitely clinical value in the diagnosis on BA.The clinical value of 6 h tomographic HBS is significantly higher than that of 6 h planar HBS and 24 h planar HBS.
6.Androgen receptor isoforms in human prostatic cancer tissue and LNCaP cell line
XIA SHU-JIE ; TANG XIAO-DA ; MA QING-ZHENG
Asian Journal of Andrology 2001;3(3):223-225
Aim: To investigate the androgen receptor (AR) isoform expressions in human prostatic cancer tissue and LNCaP cell line. Methods: With high resolution isoelectric focusing (IEF) method we demonstrated the different expressions of AR isoforms in human prostatic cancer tissues and LNCaP cell line. Results: Data were obtained from three prostatic cancer specimens and the LNCaP cell line. Three types of AR isoforms were detected with pI values at 6.5,6.0, and 5.3. For the 3 prostatic cancer specimens, 1 sample showed all the three types of AR isoforms, the second specimen expressed at 6.5 and 6.0, and the third failed to show any type of isoforms. The LNCaP cell line expressed all the three AR isoforms. Binding of 3H-dihydrotestosterone (3H-DHT) to these three isoforms was inhibited by the addition ofl00-fold excess of DHT or testosterone, while not by progesterone, oestradiol and diethylstilboestrol. Conclusion: The expression of AR isofonns is different in different prostate cancer tissues, which may be related to the difference in the effect of anti-androgen therapy in different patients.
7.Neural network-based computer-aided diagnosis in distinguishing malignant from benign solitary pulmonary nodules by computed tomography.
Hui CHEN ; Xiao-Hua WANG ; Da-Qing MA ; Bin-Rong MA
Chinese Medical Journal 2007;120(14):1211-1215
BACKGROUNDComputer-aided diagnosis (CAD) of lung cancer is the subject of many current researches. Statistical methods and artificial neural networks have been applied to more quantitatively characterize solitary pulmonary nodules (SPNs). In this study, we developed a CAD scheme based on an artificial neural network to distinguish malignant from benign SPNs on thin-section computed tomography (CT) images, and investigated how the CAD scheme can help radiologists with different levels of experience make diagnostic decisions.
METHODSTwo hundred thin-section CT images of SPNs with proven diagnoses (135 small peripheral lung cancers and 65 benign nodules) were analyzed. Three clinical features and nine CT signs of each case were studied by radiologists, and the indices of qualitative diagnosis were quantified. One hundred and forty nodules were selected randomly to form training samples, on which the neural network model was built. The remaining 60 nodules, forming test samples, were presented to 9 radiologists with 3 - 20 years of clinical experience, accompanied by standard reference images. The radiologists were asked to determine whether a nodule was malignant or benign first without and then with CAD output. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis.
RESULTSCAD outputs on test samples had higher agreement with pathological diagnoses (Kappa = 0.841, P < 0.001). Compared with diagnostic results without CAD output, the average area under the ROC curve with CAD output was 0.96 (P < 0.001) for junior radiologists, 0.94 (P = 0.014) for secondary radiologists and 0.96 (P = 0.221) for senior radiologists, respectively. The differences in diagnostic performance with CAD output among the three levels of radiologists were not statistically significant (P = 0.584, 0.920 and 0.707, respectively).
CONCLUSIONSThis CAD scheme based on an artificial neural network could improve diagnostic performance and assist radiologists in distinguishing malignant from benign SPNs on thin-section CT images.
Adult ; Aged ; Aged, 80 and over ; Diagnosis, Differential ; Female ; Humans ; Lung ; diagnostic imaging ; Lung Neoplasms ; diagnostic imaging ; Male ; Middle Aged ; Neural Networks (Computer) ; ROC Curve ; Radiographic Image Interpretation, Computer-Assisted ; Solitary Pulmonary Nodule ; diagnostic imaging ; Tomography, X-Ray Computed ; methods
8.Long-Term Results of a Prospective Randomized Trial Comparing Neoadjuvant Chemotherapy Plus Radiotherapy with Radiotherapy Alone for Patients with Locoregionally Advanced Nasopharyngeal Carcinoma
Jun MA ; Hai-Qiang MAI ; Ming-Huang HONG ; Hua-Qing MIN ; Zhi-Da MAO ; Nian-Ji CUI
Chinese Journal of Cancer 2001;20(5):503-510
Objective: A prospective randomized trial was performed to evaluate the contribution of neoadjuvant chemotherapy in the patients with locoregionally advanced nasopharyngeal carcinoma. Methods: The patients with locoregionally advanced nasopharyngeal carcinoma were treated with either radiotherapy alone (RT group) or neoadjuvant chemotherapy plus radiotherapy (CT/RT group). Neoadjuvant chemotherapy consisting of 2-3 cycles of cisplatin (20 mg/m2 on Day 1 to Day 5), bleomycin (7 mg/m2 on Day 1 and Day 5), and 5-FU (500 mg/m2 on Day 1 to Day 5) followed by radiotherapy was given to CT/RT group. All patients were treated in a uniform definitive-intent radiation therapy in two groups. Results: From 1992 to 1993, 457 patients were enrolled and 440 patients (221 in RT group, 219 in CT/RT group) were assessable. The 5-year overall survival (OS) rates were 62% for CT/RT group and 55% for RT group (P=0.1335); The 5-year relapse free survival rate was 48% versus 58% , respectively (P=0.0539). The 5-year free local recurrence (FLR) rate was 82% for CT/RT group, 74% for RT group (P=0.0412). There was no significant difference in free distant metastasis (FDM) between two treatment groups (CT/RT group, 79% ; RT group, 75% ; P=0.4177). Subgroup analyses showed that neoadjuvant chemotherapy improved local control in patients with T3-4 disease, and had no effect in preventing distant metastases in patients with N2-3 disease. Conclusion: Despite improving FLR and RFS, neoadjuvant chemotherapy and radiatherapy failed to gain other survival benefit or reduce distant metastases in patients with locoregionally advanced nasopharyngeal carcinoma. The indication for neoadjuvant chemotherapy is proposed.
9.Protective effect of ischemic postconditioning on ischemic reperfusion injury of rat liver graft.
Nan WANG ; Qing-jiu MA ; Jian-guo LU ; Yan-kui CHU ; Da-nian LAI
Chinese Journal of Surgery 2005;43(23):1533-1536
OBJECTIVETo observe the protective effect of ischemic postconditioning on ischemic reperfusion injury of rat liver graft and to investigate the possible mechanism.
METHODSMale Sprague Dawley rats were used as donors and recipients of orthotopic liver transplantation, and the period of cold preservation and anhepatic phase were 100 min and 18 min, respectively. Sixty rats were randomly divided into three groups, twelve rats in control group, twenty-four rats in ischemic reperfusion injury group and ischemic postconditioning group respectively. Control group is sham operation group, only the ligaments around liver were cut off; donor livers in ischemic reperfusion injury group were infused through portal vein with heparinized saline before harvested; ischemic postconditioning group: at very onset of reperfusion after donor liver was implanted, several brief reperfusion-ischemia were given before persistent reperfusion of portal vein. Half recipients of ischemic reperfusion injury group and ischemic postconditioning group were taken blood samples and hepatic tissue samples after 2 hours of reperfusion of liver graft. Rest recipients were taken samples of hepatic tissue after 6 hours of reperfusion. Recipients of control group were taken blood and hepatic tissue samples at corresponding time after abdomen was sutured.
RESULTSCompared with ischemic reperfusion injury group, liver functional parameters, cytokines and peroxidized products contents were lower in ischemic postconditioning group (P < 0.05); meanwhile, the antioxidases contents of hepatic tissue were higher in ischemic postconditioning group than those in ischemic reperfusion injury group (P < 0.05).
CONCLUSIONSIschemic postconditioning could relieve the ischemic reperfusion injury of rat liver graft. Through improving antioxidation capability and cutting down cytokines contents, ischemic postconditioning could apply its protective effect.
Animals ; Glutathione Peroxidase ; metabolism ; Leukocyte Elastase ; blood ; Liver ; blood supply ; metabolism ; Liver Transplantation ; Male ; Malondialdehyde ; metabolism ; Peroxidase ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism ; prevention & control ; Superoxide Dismutase ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism
10.Value of positron emission tomography-CT imaging combined with continual detection of CA_(125) in serum for diagnosis of early asymptomatic recurrence of epithelial ovarian carcinoma
Xiu-Gui SHENG ; Xiao-Ling ZHANG ; Zheng FU ; Hui-Qin LI ; Qing-Shui LI ; Zhi-Fang MA ; Da-Peng LI ; Zhen-Yun CHEN ;
Chinese Journal of Obstetrics and Gynecology 2001;0(07):-
Objective To evaluate the value of positron emission tomography(PET)-CT imaging combined with continual detection of CA_(125)in serum for diagnosis of early recurrent ovarian epithelial carcinoma.Methods Twenty six patients received PET-CT imaging,who were all diagnosed as primary epithelial ovarian cancer of stage Ⅱ-Ⅳ and had complete remission after cytoreductive surgery and multiple courses of chemotherapy in Shandong Provincial Cancer Hospital.After a steady period,all patients experienced progressive rising of CA_(125)values 3 times in 2 months.But no positive lesion was found by CT, or although suspicious positive focus was found,the recurrent and(or)metastatic extent was not definite. Out of 26 patients,16 were delivered rechemotherapy and(or)radiotherapy,and 10 received re- cytoreductive surgery.Results(1)Of 26 patients,the value of CA_(125)was more than 35 kU/L in 17,and in 14 of 17,pelvic or abdominal cavity recurrence was diagnosed by CT and PET-CT,and 4 showed simuhaneously distant metastasis on PET-CT.In the remaining 3 patients of which CT findings were negative,2 had pelvic and abdominal cavity recurrence,and one had bone metastasis on PET-CT.Of 9 patients with progressive rising CA_(125)levels but the value was less than cut-off(